Objectivity/DB consists of shared libraries, several servers, and a set of administrative tools. The shared libraries and servers provide storage and retrieval of local and distributed data, and ensure data integrity through transaction Objectivity/DB is a database software library that is linked with the application program instead of using a separate data server process. It has C++, Java, .NET and Smalltalk application programming interfaces. It also supports SQL and XML. It includes database design and administration tools that plug in to an Eclipse framework.

Features include:- Storing any .NET object without implementing any interface and without inheriting from a specially designed class- LINQ queries for any type- Queries based on SQL- In-memory database support for high speed data processing- Returns the objects in their native form, as a single object or as an enumeration- Supports arrays in queries- Expressions and functions in queries- Flexible sorting- Regular Expressions support in queries- Indexes- Bulk inserts and updates- Generic object support- Inheritance support in queries- Client/server architecture- Parallel and independent query execution for multiple users- Windows authentication- Both Server and client are implemented in 32- and 64-bit architectures- Unique identifier for any object within a database- Native GUID identifiers support- Approximate matching with ALMOST keyword

Features include:- objects are stored as they are without any conversion/mapping- LINQ is the only query engine that can be used to retrieve objects or members of objects from database- full POCO support (not mandatory to inherit from a base class)- assembly is about 130KB- zero config- automatic object schema refactoring- import/export from/to XML- thread safe- has features from relational database systems like JOINs- embedded database engine- any object has unique OID (object identifier) for its Type- runs on Silverlight by storing objects into IsolatedStorage on client machine or on Silverlight 4 is able to store database files on local disk of client machine in OOB mode- runs on Windows Phone 7

Features include:- Any serializeable object can be persisted- Scalable (billions of object is no issue)- High Performance (see benchmarks on Compare page)- LINQ queries- Indexes- Choice of Pessimistic locking and Optimistic locking- Compression (optional at page level, controlled by user for each database location) - Encryption (optional at page level, controlled by user for each database location) - Composite Object Identifier (Database-Page-Slot)- Support for distribution to almost unlimited number of hosts- Support for millions of database files- Embeddable- Optional automatic backup of all data in a database location to a backup location- Variable page size (from a few bytes to GB’s depending on how many objects and their sizes). Databases and pages do not contain any unused bytes (unlike fixed size database pages), only space for allocated objects- Auto recovery build in (no journal files required) - Windows authentication